Dietary Nitrate (Beetroot)
Inorganic nitrate, usually from concentrated beetroot juice, reduced in the body to nitrite and nitric oxide. Improves exercise economy and endurance performance, with the strongest effects in recreationally trained rather than elite athletes. A well-studied, food-derived ergogenic aid.
01 Overview
Dietary nitrate is converted by oral bacteria and tissue enzymes to nitrite and then nitric oxide, a signalling molecule affecting blood flow, mitochondrial efficiency and muscle contractile function. Beetroot juice is the most common vehicle in research.
Controlled trials and meta-analyses show improved exercise economy (lower oxygen cost at a given intensity) and modest endurance gains, particularly in continuous and time-trial efforts. Benefits are generally larger in recreationally active people than in highly trained athletes, whose baseline nitric-oxide handling is already optimised. Antibacterial mouthwash abolishes the effect by killing the oral bacteria needed for the first reduction step.
02 Mechanism
Reduced via the nitrate-nitrite-nitric oxide pathway (requiring oral bacteria), enhancing blood flow, mitochondrial efficiency and calcium handling to lower the oxygen cost of exercise.
03 Dosing
| Tier | Dose | Route | Notes |
|---|---|---|---|
| Common | 300–600 mg | Oral | ~6-13 mmol nitrate (roughly 300-600 mg) taken 2-3 h pre-exercise; multi-day loading may enhance effect. |
04 Effects
| Effect | Magnitude | Evidence | |
|---|---|---|---|
| Improved exercise economyReduces the oxygen cost of submaximal exercise, a robust and repeatable finding. | Lower O2 cost at fixed intensity | Clinical | |
| Improved endurance performanceModest improvements in endurance and time-trial performance, largest in recreationally trained individuals. | ~1-3% in time-trials | Clinical |
05 Side effects
| Effect | Severity | Frequency | Evidence | Countermeasures |
|---|---|---|---|---|
| Red/pink urine and stool (beeturia)Harmless red discolouration of urine or stool from beetroot pigments. | Mild | Frequent with beetroot | Observational | |
| Gastrointestinal upsetMild GI discomfort from concentrated juice. | Mild | Occasional | Observational |